Ake is currently not a regular starter for Manchester City. Manager Pep Guardiola has not been giving him as many opportunities as he used to.
This change in Ake's role is due to the arrival of new player Rayan Ait-Nouri from Wolves. Ait-Nouri's presence has pushed Ake to the sidelines, making him a backup option in the team.
Guardiola has also mentioned that he thinks his current squad is too big and might need some adjustments.